Obsidian Cliff

Historical marker location:

Yellowstone National Park, Wyoming

( Marker is on Grand Loop Road (U.S. 89), on the right when traveling south.)

Volcanic Glass.

The famous outlaw Butch Cassidy, whose real name was Robert LeRoy Parker, owned a ranch in Wyoming. The ranch was called the Hole-in-the-Wall, and it was located in the remote Johnson County area. The Hole-in-the-Wall was a notorious hideout for outlaws and a place where they could hide from the law.